


Thicker than Water

by showurselfelsa (kanshou87)



Category: Fate/stay night - All Media Types, Frozen (Disney Movies)
Genre: !ServantElsa, !magicianAnna, Caster Elsa, Discord: Elsanna Shenanigans (Disney), Elsa harbours a secret, Elsanna Week 2021 (Disney), F/F, Fate/stay night & Related Fandoms References, Holy Grail War (Fate), Hurt/Comfort, Implied/Referenced Incest, Magic, Minor Anna/Kristoff (Disney), Protective Anna (Disney), Reincarnation, Summoning Circles, Unrequited Love, based on fanart
Language: English
Status: In-Progress
Published: 2021-02-02
Updated: 2021-02-02
Packaged: 2021-03-13 15:34:26
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,314
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29155908
Author URL: https://archiveofourown.org/users/kanshou87/pseuds/showurselfelsa
Summary: Written based on Elsanna Week 2021 Prompts - ReunionAnatasia, the last heir of Ainsworth was pleasantly surprised by the arrival of her newly summoned magic familiar, Caster. [!MageAnna x !ServantElsa]
Relationships: Anna & Elsa (Disney), Anna/Elsa (Disney)
Comments: 11
Kudos: 25





	Thicker than Water

**Author's Note:**

> This three part fic is inspired by @frozen_1022 (twitter link: https://twitter.com/frozen_1022/status/1337469084259119104?s=20) art where Anna summoned Elsa using a summoning spell. I took a step further and adopted the whole Fate Stay Night concept loosely into this story. Shoutout to JYN044 for beta-ing this piece and cs6ice for actively helping me out with the storyline.

Art credit to @[frozen_1022](https://twitter.com/frozen_1022/status/1337469084259119104?s=20)

_ xxx December 1843 xxx _

_ Kingdom of Arendelle  _

Darkening clouds gathered in the sky, forming a sombre overcast over the Kingdom of Arendelle. Water-filled bellies rumbled, eager to be released; their desire made clear by occasional flashes of lightning. Strong winds joined in the symphony, wailing in the background like mad animals. A heavy downpour followed suit; falling raindrops drummed noisily on the rooftops and windows of Arendellian houses. 

Spring was one of Elsa’s favourite things. It represented new beginnings - welcoming new life after a harsh winter. However, that was about to change for Elsa as she kneeled next to her sister in the heart of Arendelle’s castle. 

Cold was something that never bothered her; the woman was a living manifestation of ice and snow, after all. Holding her little sister's icy, frail hand bitterly reminded the elder of how powerless she was against the cold despite being the master of all elements. Elsa herself had once experienced Death’s cold embrace in the depths of Ahtohallan but had been lucky to escape unscatched. Death’s touch was unforgiving, like the one surrounding her younger sister right now. 

Elsa squeezed her eyes shut, reining in her devastation. 

They were supposed to be parts of a bridge, weren't they? If so, why was Anna not spared? Shouldn't Elsa’s immortality be extended to her by virtue of her magic? 

She clenched her hand into a tight fist, bunching up the material on her lap. Full blown regret washed over her. If she had known of this, Elsa would have stayed. 

_ Your selfishness hurt her again. And this time it cannot be undone.  _

"Elsa?"

Glossy teal eyes sparkled under the dim lighting, sending chills down Elsa's spine.  _ How can she sound so calm when the end is only a hair’s breadth away?  _

" _ Elsa _ ,” the tender voice called, subtly commanding attention. 

The elder sibling wiped her tears away. "Yes, I am here, Anna." She tensed a little when her sister squeezed her hand with little effort, despite her weakened state. 

"Thank you for being in my life, Elsa." All emotional barriers were broken in an instant, shattering into millions of tears. Elsa could not bear the undertone of finality in her sibling's words. 

"Anna, you can't... What would I do without you?" 

A gentle finger brushed away the elder's bangs. 

"You will be fine, Elsa." 

Elsa froze, suddenly feeling like a helpless, scared child. 

_ That's what Papa said before he passed away.  _

"You will continue to do great things like you did before. Our kingdom will continue to flourish under your stewardship..." Anna trailed off when she noticed Elsa was not paying attention, lost in her sorrow. The younger sighed and tugged her sister's sleeve.

"Come closer." 

The blonde silently obeyed, meeting her sister halfway as their foreheads touched. The contact seemed to have a calming effect on Elsa. Her incessant crying simmered into sobs. 

“Listen. Elsa. You will always have me, even if I’m gone...” Anna continued, trembling hands guiding Elsa to her beating heart. “I will be here. Just like Mama and Papa.” 

“Anna…” 

A voice echoed inside of her. 

_ You need to let her know how you feel, before it’s too late.  _

"Promise me, Elsa. Promise me, you will continue to live your life."

Elsa gritted her teeth. 

Her sister’s pleading eyes took away her conflicting thoughts. Not in a million years she could deny Anna her wish - not now, not ever. Her baby sister had had Elsa wrapped around her finger since she set eyes on her in Mama’s cot. Elsa’s arms came around Anna’s frame, head buried into the nape of her neck. She inhaled deeply, letting her mind imprint this warmth into memory. She pushed back to her inner voice. 

_ No, I will not taint her with my selfish desire. I have done enough damage as it is.  _

“I will, Anna. I promise.” 

The red-head burst into fits, clenching her chest as she coughed.

“Anna!” 

The younger sibling waved her hand. 

“I’m okay. I just need some rest.” 

Anna gestured at Elsa, pointing at the picture frame resting on the nightstand. Inside the casing was a group picture, featuring a much younger Anna holding a baby in her arms, flanked by an excited Olaf and Sven. Kristoff had his hand around her shoulders, looking proudly at the bundle of joy with Elsa standing beside him. Tears welled in the younger eyes as she gazed at the picture frame; few teardrops fell and splashed on the glass cover.

Elsa’s heart broke, squeezing her sister’s hand to offer support. 

“I miss them so much, Elsa,” she admitted, hugging the frame to her chest. The weight of grief was still heavy in the recesses of Anna’s mind despite it happening almost two decades ago. 

The elder weeped. "I'm so sorry." 

Elsa remembered the day clearly. It was a planned family trip that went horribly wrong. The monarchs wanted to kidnap her for a surprise. Anna was assigned to get Elsa from the forest whilst Kristoff and little Aren busied themselves with the preparation. The elder was elated when Anna had given the news to her; she offered her sister a ride back on Nokk.

Her happiness was short-lived; an ashened Kai had broken down when he received the sisters at the bank. An unexpected avalanche occurred near the North Mountain and buried everyone underneath - no survivors were found. 

Elsa was horrified at the news. Pang of guilt gnawed on her insides - she was the reason for the kingdom's tragedy. How could she stay when her presence constantly reminded Anna of her loss? At the first light of dawn, a day after the funeral procession was completed, the frightened blonde jumped on Nokk and fled to the Enchanted Forest.

Dark times befell the kingdom. For almost two years, the citizens mourned for their King and the loss of their future heir but it took twice as long for the new Queen to overcome her grief. Arendelle closed its doors once more, this time isolating itself from the rest of the world. Elsa never returned since; she lived in Ahtohallan in self exile. Had it not been for Olaf’s rebelliousness and persistence, the sisters would have been estranged for their remaining lives. 

And now, just when both of them had made up, Anna had fallen terribly ill; her body succumbed to a sickness which had no cure, not even magic. Elsa's lips pursed into a thin line. Had she remained her stand and stayed in the forest, none of this would have happened. 

“Elsa, can you do the magic?” 

_ Do the magic! Do the magic! _

At one moment Elsa felt like she was being transported back to their shared bedroom, performing magic tricks underneath the blanket. She would never understand her little sister’s fascination with magic. Magic was the very thing that almost took her sister's life away during the Great Thaw and now was failing to save her. Only Ahtohallan knew if this cruel fate was her punishment for running away. 

“Very well.”

The elder summoned a snowball in her palm and threw it into the air. It bursted into speckles of flurries, bringing a smile on the younger’s tired face. The latter opened her hand, catching a few flakes into her palm. 

“Thank you, Elsa. They're beautiful.” 

“Anytime, Anna. Anything for you.” 

_ It’s the least I could do after what I have put you through.  _

Anna peered into Elsa’s eyes, asking timidly, “Promise me you’ll be here when I wake up?” 

Guilt stabbed her heart. 

_ She thinks you are going to run away again.  _

Elsa gripped her sister’s hand and held it to her chest. 

“I will be here. I am not going anyway.“

A gust of rogue wind pried open the windows, snuffing out the candle in its way. 

And with it went Anna’s last breath. 

xxx Dec 2020 xxx

Anatasia scanned the area. None of the buildings had the name RV on it. She unfolded the paper in her hand and glanced at the street plate. It read: 

768 Cyclone Street.

The name matched with the location denoted by a X mark in the hand drawn map. She peered on the note again.

_ The answer must be here somewhere. I am sure of it.  _

Anatasia’s quest to find this mysterious place had started after her eighteen birthday. A mysterious man who claimed to be a lawyer had visited her at the orphanage one day and dropped a life-changing bombshell on her. A will reading session revealed that she was the sole heiress of the Ainsworth family. Her parents’ unfortunate passing following an accident had led her to inherit her family’s riches and assets overnight, including a century-old mansion with a width spanning across two football fields. The lawyer had been tight-lipped about the details of her parents’ death when she asked, which piqued Anatasia’s interest about her family. An accidental discovery of a hidden room during her tour in the Ainsworth mansion further stirred her curiosity. The place was well hidden behind a row of bookshelves in the private study. What she found inside told her that her parents were not simple folks, evidenced by the odd assortment of books and items that made her fine hair stand. The key to unravel this mystery was the note in her hand which she found in a hardbound journal. Almost half of the journal was destroyed, pages completely ripped from its spine. The only readable page had a short entry. It read:

_ January 2019 _

_ "They have already breached the barrier, I can feel their presence. I hope we can stop this catastrophe and reunite with our daughter again. Until then, I pray that the Lord will continue to protect her from harm, wherever she is."  _

_ I.A.  _

Blotches of dried blood stained the written page, making her stomach lurch. There was definitely more than met the eyes and this small clue would help to find out her family’s secrets.

“Hello, Miss. Are you lost?” A hoarse voice spoke, jolted her from her musings. 

A stout man with receding hairline came into her vision. Anatasia swallowed at the sight of a large scar running through his face. His sleeves were rolled up to his elbow, revealing another scar on his forearm. Something about this person spelt danger. 

“I was looking for a place called RV. Are you familiar with it?” 

The man’s thick eyebrow arched. 

“What business do you have with my shop?” 

Anatasia beamed. 

All her fear was momentarily forgotten. She took the man’s right hand into hers, squealing like an excited child. 

“OMG! I’m so glad I bumped into you,” she shook his hand. "I hope you can help me out, Mr…" 

"Pablo. You can call me Pabbie."

"Nice to meet you, Pabbie. I'm Anatasia Ainsworth."

His eyes widened.

"Agnarr sent you?" 

Anatasia shook her head. 

"No...he didn't." She grimaced, "My parents, they passed away in an accident." 

"I'm sorry to hear that." 

Anatasia sighed. “I know this is going to sound bad but I don’t know anything about them. I just recently found out about the Ainsworths and they were not...helpful. So, I came to look for answers.” She handed Pabbie the note. “I found this in the basement.” 

The man inspected the note and nodded.

“Yes, your parents came to me a long time ago for consultation. Let’s speak further at my place.” 

She gasped when the buildings shimmered away at a wave of Pabbie’s hand, revealing a shop.

Pabbie clutched his waist,“Well, what are you standing there?” He waved.

”Come on, in.” 

_ Ainsworth’s Mansion, December 22 _

Strong wind slammed the door behind Anatasia. Her teeth chattered vigorously despite the double layer of clothing; it could not stop the winter cold from seeping in her bones. She basked in the warm air blowing from the mansion's heater, mitten hands rubbing her forearms to generate additional heat. She glanced at the giant family portrait hanging on the wall. 

In the past two months her life had taken a new turn. She went from an orphan to heiress of the most influential family in both wealth and magic. And now, she was on track to follow in her parents' footsteps and defend the world from a fatal end from iits enemies. 

_ "You mother and father were chosen to be contenders for the Holy Grail war." _

The Holy Grail War. A battle royale among seven chosen magicians using familiars of Heroic spirits, called Servants. The winner of the war would get a chance to have their wish granted, be it good or bad.

_ "Servants are divided into seven classes - Saber, Archer, Rider, Caster, Berserker, Assassin and Lancer. Mages don't choose their Servants. It all depends on the time and personality of the summoner." _

_ "How would I know when the right time is?" _

_ "It's not my place to tell. You will know." _

Pabbie was right. Now a strong urge pulsed inside her veins, calling her to the study. She quickly grabbed a pen knife and rushed to the hidden room. 

Anatasia smiled to herself. She wiped off some blood residue from her forefinger with a tissue and stood to admire her handiwork. A summoning circle etched on the dark floorboard, its perimeter spanning a quarter of the basement. She turned to look at the grandfather clock. It read 9.30 a.m. 

Perfect. 

The teenager padded around the circle and reached out for a handbound book on the desktop. She licked her thumb and flicked a few pages. Teal eyes focus diligently on the scribbled list of items. 

  1. Summoning circle - Checked
  2. Catalyst 



She looked at the second item and thought for a while.

_ “The Catalyst is something which is related to the Servant that you wish to summon.”  _

Pabbie had said those words when he handed her change. Ever since that fateful meeting, the Rocky Valley Magic Shop, RV in shot, had become her favourite hang out place after school. Anatasia benefited a lot from her frequent visits - Pabbie taught her how to hone her untapped magic. Being a big fan of magic had also helped her to accelerate her learning. Aside from the lessons, she had grown fond of the place. Mind you, RV was not like one of those trick stores that sold cheap magic tricks or prank guide books. It was a place of mystery, housing many collections from the past - antiques and artifacts that were lost in time placed on dusty shelves; too precious to leave their home. Although they were not for sale, the man was generous enough to lend her the stuff from the shop for Anatasia to practice her magic. 

The red-head shoved her hand into her pocket and pulled out a pouch. She unlaced it revealing a few items - a quill feather pen, a maple leaf and some diamond shaped gemstones. She placed them in the centre of the circle as per Pabbie’s instructions and stepped back. Her finger pointed at the last item on the list. 

  1. Summoning item and incantation 



Anatasia retrieved a sunflower brooch from her desk drawer and held it against her chest. She took a deep breath and recited the incantation. 

_ Let silver and steel be the essence. _

_ Let stone and the archduke of contracts be the foundation  _

_ Let blue the colour I pay tribute to  _

_ Let rise a wall against the wind that shall fall _

The pentagon in the summoning circle began to glow a bright white hue. A slight breeze caressed her freckled cheeks. 

_ Let the four cardinal gates close. _

_ Let the three-forked road from the crown reaching unto the Kingdom rotate. _

_ I hereby declare. _

_ Your body shall serve under me. _

_ My fate shall be your weapon. _

_ Submit to the beckoning of the Holy Grail  _

_ If you will submit to this will and this reason…Then answer! _

Her skin prickled at the sudden chill. She could feel the room’s temperature dropping drastically, as though she was locked in a freezer. A few snowflakes appeared and suspended in the air. 

_ An oath shall be sworn here! _

_ I shall attain all virtues of all of Heaven.  _

_ I shall have dominion over all evils of all of Hell!  _

_ From the Seventh Heaven, attended to by three greet words of power, _

_ Come forth from the ring of restraints, _

_ Protector of the Holy Balance!  _

A strong gust of wind emerged from the summoning circle, forming a rambunctious whirlwind that lashed out at everything in its path. Stacks of neatly arranged papers dispersed in the air, dancing to the airflow. Lighter furniture was overturned. A powerful light shot up at the circumference, making her eyes water. Anatasia averted her gaze when the brightness became intense. A deafening explosion followed, throwing her to the edge of the basement. 

When Anatasia came to, she saw a woman stepping out of the circle. She wore a translucent long dress flanked with twin transparent trains that swept across the ground. Patterns of diamond shaped crystals adorned her neckline, accentuating her slender body. Her hair was platinum blond; locks curled in a natural flow that almost reached her waist. The woman’s ethereal looks took Anatasia’s breath away - the lady could totally pass as a goddess.

Perplexed icy blues found Anatasia’s bewildered teal. 

“Erm...Hi…” 

Anatasia’s heart raced. 

_ Gosh, even her voice sounds angelic.  _

The red-hair cleared her throat, willing herself not too blush. 

“Hi, I’m Anatasia. Descendant of the Ainsworth magic bloodline. Nice to meet you. You are…?”

The blonde haired woman blinked out of her stupor. 

“Nice to meet you too. I’m El...” she paused and corrected herself…”I’m Caster.” 

Anatasia rested her hands on her waist, “Fancy name. Do you have something that is...distinctively you?”

The woman tapped her chin for a moment to ponder. “Not that I can think of…”

“Snowflake!”

Caster made a face, not understanding. 

“Yes, I have decided. I will call you Snowflake.” The girl scratched her head. “There were snowflakes in the air when I summoned you, so it’s natural to name you according to your abilities.” she reasoned enthusiastically. 

“Well then...” 

The woman advanced and dropped on one knee. 

“I hereby pledge myself to Anatasia Ainsworth and to serve you as my Master.” 

Anatasia leaned in, capturing the other’s hand in hers. 

“I accept your pledge. Let these words form a bond between Master and Servant.” 

Three strokes of marks appeared on the back of Anatasia’s hand, mirroring a Crocus flower. 

“Wow! What are these?” Anatasia asked.

“Summoning tokens. Masters have three tokens that you use to command us Servants to your will, even if we are against it.” 

Anatasia crossed her arms against her chest. 

“That’s horrible. I will never do that.” 

Snowflake looked up when the girl clasped her hand, brushing her thumb against her knuckles. 

“Snowflake, you may be my Servant but never my tool. I will protect you.” 

The woman shuddered. A smile crooked on Snowflake’s face as her Master rambled on about magic, memories of a particular person playing in her head. Perhaps, this time she could get things right. Her musings were abruptly interrupted by a gentle tug of her hand. 

“Come on, Snowflake. I’ll show you around.” 

The Servant’s wide smile made Anatasia’s heart blossom. The young mage felt somewhat connected to the blonde, as though she had known her all her life.  _ Perhaps it was an after effect of their contract? _ She quickly buried her speculation and shifted her focus on her new friend. 

“I bet you are hungry. Would you like a cup of hot chocolate?” 

Anatasia swore she saw the woman’s eyes lit up. 

“That will be lovely, Master.”

The young mage waved her hands frantically, face flushed in embarrassment. 

“No, no... Call me Ana, please. We are equals, you and I.”

“Alright. Lead the way, Ana.” 

The crimson shade deepened as Anatasia noticed how eloquently her name sounded. 

_ Yup, I definitely need that cup of chocolate.  _

To be continued.

**Author's Note:**

> Hope you enjoy it. Do let me know what you think in the comment box below. Thanks!


End file.
